Synthesis and Properties of Vinyl Ether and Acrylonitrile Copolymers

Abstract

AbstractThe radical copolymerizations of vinyl ethers, including ethylene glycol monovinyl ether (HEVE) and isobutyl vinyl ether (IBVE), and acrylonitrile (AN) are investigated. The reactivity ratios of comonomers are evaluated by Fineman–Ross (rHEVE = 0.032 and rAN = 1.054, and rIBVE = 0.031 and rAN = 13.984) and Kelen–Tudos (rHEVE = 0.001 and rAN = 1.036, and rIBVE = 0.032 and rAN = 13.981) methods, respectively. The conversions of HEVE and IBVE under similar conditions also support that HEVE has a higher reactivity than that of IBVE. A series of poly(HEVE‐co‐AN)s (Mn from 56 000 to 110 000) and poly(IBVE‐co‐AN)s (Mn from 52 000 to 97 000) with random sequential structure are prepared. Furthermore, the glass transitional temperatures of poly(vinyl ether‐co‐AN)s decrease with the increase of vinyl ether units in the copolymers. Thermal stability of poly(vinyl ether‐co‐AN)s is comparable, which is slightly affected by vinyl ether contents. Poly(HEVE‐co‐AN)s possess a two‐stage weight loss (one around 230 °C, and the other around 300 °C), and poly(IBVE‐co‐AN)s decompose at around 350 °C with one stage. In addition, the poly(HEVE‐co‐AN)s demonstrate a good hydrophilicity of which the average of static water contact angles decrease from 85.4° to 62.4° with the HEVE units increased from 8% to 33%.